Conventionally, there is known a system including terminal devices and a host computer, which are interconnected through a network, and each terminal device is capable of using a function of the host computer through the network. An example of such a system is disclosed in Japanese Patent Provisional Publication No. H09-238215. In this system, bit data representing, for example, command codes for control and density of images is sent from the terminal device to the host computer, which analyzes the received command codes and performs image processing utilizing image editing functions specified for the image data and returns the processed data to the terminal device for printing.
In this system, the terminal device receives the service provided by the host computer to process the image data so that the terminal device is capable of printing the image. In such a system, the terminal device should be provided with a function to receive the service. That is, in the above example, the terminal device should be provided with a printing unit.
In the above example, as the terminal device is provided with the printing unit, it can receive the image data processing service provided by the host computer. According to the conventional system, if a user of the terminal device intends to receive another service requiring an un-equipped function of the terminal device, the terminal device cannot receive the service.